During his trip to Portugal for the centenary of the Fatima Marian apparitions next month, Pope Francis will canonize visionaries Francisco and Jacinta Marto, making them the youngest non-martyrs to ever be declared saints.

The children will be canonized during Pope Francis’ May 13 Mass in Fatima. The decision for the date was made during a April 20 consistory of cardinals, which also voted on the dates of four other canonizations, in addition to that of Francisco and Jacinta, that will take place this year.

Some martyrs who will soon be saints are diocesan priests Andrea de Soveral and Ambrogio Francesco Ferro, and layman Matteo Moreira, killed in hatred of the faith in Brazil in 1645; and three teenagers – Cristóbal, Antonio, and Juan – killed in hatred of the faith in Mexico in 1529, who will be canonized October 15.

Bl. Angelo da Acri, a Capuchin priest who died in October 1739, and Faustino Míguez, a Piarist priest who founded the Calasanziano Institute of the Daughters of the Divine Shepherd, will also be canonized October 15.

Cardinal Jose Saraiva Martins, the Prefect Emeritus of the Congregation for the Causes of Saints, is the man who was largely responsible for advancing the visionaries’ cause, paving the way for them to become the first canonized children who were not martyred.

Previously, the Portuguese cardinal told CNA, children were not beatified, due to the belief “that children didn’t yet have the ability to practice Christian heroic virtue like adults.”

But that all changed when the cause for Francisco and Jacinta Marto arrived on his desk.

Francisco, 11, and Jacinta, 10, became the youngest non-martyr children in the history of the Church to be beatified when on May 13, 2000, the 83rd anniversary of the first apparition of Our Lady at Fatima, Pope John Paul II proclaimed them “Blessed,” officially showing that young children can become Saints.

The brother and sister, who tended to their family’s sheep with their cousin Lucia Santo in the fields of Fatima, Portugal, witnessed the apparitions of Mary now commonly known as Our Lady of Fatima.

During the first apparition, which took place May 13, 1917, Our Lady asked the three children to pray the Rosary and make sacrifices for the conversion of sinners. The children did this and were known to pray often, giving their lunch to beggars and going without food themselves. They offered up their sacrifices and even refrained from drinking water on hot days.

When Francisco and Jacinta became seriously ill with the Spanish flu in October 1918, Mary appeared to them and said she would to take them to heaven soon.

Bed-ridden, Francisco requested and received his first Communion. The following day, Francisco died, April 4, 1919. Jacinta suffered a long illness and was eventually transferred to a Lisbon hospital, where she underwent an operation for an abscess in her chest. However, her health did not improve and she died Feb. 20, 1920.

Francisco and Jacinta “practiced Christian virtue in a heroic way,” Cardinal Martins said, explaining that among other things, one of the most obvious moments in which this virtue was apparent for him was when the three shepherd children were arrested and intimidated by their mayor on August 13, 1917.

Government stability in Portugal was rocky following the revolution and coup d’état that led to the overthrow of the monarchy and subsequent establishment of the First Portuguese Republic in 1910.

A new liberal constitution separating Church and state was drafted under the influence of Freemasonry, which sought to omit the faith – which for many was the backbone of Portuguese culture and society – from public life.

It was in this context that, after catching wind of the Virgin Mary’s appearance to Francisco, Jacinta and Lucia, district Mayor Artur de Oliveira Santos had the children arrested on the day Mary was to appear to them, and threatened to boil them in hot oil unless they would confess to inventing the apparitions.

At one point in the conversation at the jailhouse, Jacinta was taken out of the room, leaving Francisco and Lucia alone. The two were told that Jacinta had been burned with hot oil, and that if they didn’t lie, the same would happen to them.

However, instead of caving to the pressure, the children said: “you can do whatever you want, but we cannot tell a lie. Do whatever you want to us, burn us with oil, but we cannot tell a lie.”

“This was the virtue of these children,” Cardinal Martins said, noting that to accept death rather than tell a lie is “more heroic than many adults.”

“There’s a lot to say on the heroicness of children,” he said, adding that “because of this I brought their cause forward.”

Cardinal Martins was also the one to bring Lucia’s cause to the Vatican following her death in 2005. The visionary had spent the remainder of her life after the apparitions as a Carmelite nun.

Typically the must be a five-year waiting period after a person dies before their cause can be brought forward. However, after only three years Martins ask that the remaining two be dismissed, and his request was granted.

Although the diocesan phase of the cause has already been finished, Cardinal Martins – who knew the visionary personally – said Lucia’s process will take much longer than that of Francisco and Jacinta not only due to her long life, but also because of the vast number of letters and other material from her writings and correspondence that needs to be examined.

The cardinal, who will be present in Fatima with the Pope during his May 12-13 visit for the centenary of the apparitions, said he views the occasion as the conclusion of a process that began with him changing a norm regarding the view of children “and their heroic virtue.”

This process is important, he said, because it means there could be other children who practiced heroic virtue that can now be canonized, so “it’s certainly something important.”

“It needs to be seen that (children) are truly capable of practicing heroic virtue,” not only in Fatima, but “in the Christian life,” he said.

Although canonizations, apart from a few exceptions, are typically held in Rome, it was only recently that beatifications began to be held outside of Rome, in the local Church which promoted the new Blessed’s cause.

This change was made by Cardinal Martins in September 2005, after receiving the approval of Benedict XVI.

In the past, a beatification Mass in Rome would be presided over by the Cardinal-Prefect of the Congregation for the Causes of Saints during the morning, with the Pope coming down to the basilica to pray to the new Blessed in the afternoon. Cardinal Martins said he decided to change this because the beatification and the canonization “are two different realities.”

“While the canonizations had a more universal dimension of the Church, the beatifications have a more local dimension, where they (the Blessed) came from,” he said, noting that this is reflected even in the words spoken during the rites for each Mass.

“Because of this, I made a distinction: the beatification in their (the Blessed’s) own church, in their diocese, and the canonizations in Rome.”

The result was “a fantastic revolution,” he said, explaining that while maybe 2-3,000 people would participate in the beatification ceremonies in Rome, hundreds of thousands started to come for the local beatification Masses of new Blessed in their home dioceses.

The cardinal said that “it’s beautiful” to see people – many times including friends and family members of new Blessed – join in honoring their countryman, asking for their intercession, and seeking to follow their example.

He believes the custom will remain like this, adding that it is beautiful particularly from the standpoint of evangelization.

“The new Blessed says to their brothers, many of whom they knew, ‘I am one of you, one like you, so you must follow my path and live the Gospel in depth’,” the cardinal said, explaining that this is “a formidable act of evangelization, and with everyone happy about the new Blessed, they’ll immediately do what they say!”

Cardinal Martins said the decision was also prompted by the emphasis placed on local Churches during the Second Vatican Council.

“I thought, one of the most effective ways to highlight the importance of local Churches is to conduct in the local diocese the beatification of one of their sons,” he said.